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Reusable Laser Launcher

A 50.0 MW laser beam energising a rocket with a jet power of 35.7 MW produces a laser energised rocket to create a 20,572 mph exhaust jet from inert material like water. This jet produces 1,741 pounds of thrust lifting a vehicle that weighs 1,358 pounds at lift off. 1,100 pounds (132 US gallons) contained in a sphere 39 inches in diameter, is energised over 12 minutes to boost the 330 pound payload to orbit aboard the 311 pound vehicle. After one orbit, the booster derbies and descends back at the launch centre, landing under laser power, 84 minutes after launch. Within 120 minutes after launch the booster is ready to go again!

On Thursday, April 6, 2017 at 2:10:06 PM UTC+12, William Mook wrote:
A 50.0 MW laser beam energising a rocket with a jet power of 35.7 MW produces a laser energised rocket to create a 20,572 mph exhaust jet from inert material like water. This jet produces 1,741 pounds of thrust lifting a vehicle that weighs 1,358 pounds at lift off. 1,100 pounds (132 US gallons) contained in a sphere 39 inches in diameter, is energised over 12 minutes to boost the 330 pound payload to orbit aboard the 311 pound vehicle. After one orbit, the booster derbies and descends back at the launch centre, landing under laser power, 84 minutes after launch. Within 120 minutes after launch the booster is ready to go again!

A satellite at an altitude of 250 miles the satellite rises 1371.3 mile on one side of the laser and sets 1371.3 miles on the other side, arcing across the sky in 9 minutes 16.3 seconds.

The laser has 9 minutes to energise the rocket for a deep space boost! Boosting a 330 pounds vehicle from 17,665 mph to 23,373 mph - puts it on course to the moon by adding a 6,708 mph delta vee. At 4 gees, it takes 75 seconds to accelerate from 17,665 mph to 23,373 mph, and covers 437.9 miles during the acceleration boost!

With a 20,571.4 mph exhaust speed 92.8 pounds of propellant is required to accelerate to that speed. 238.2 pounds sent to the vicinity of the moon.

On Tuesday, April 11, 2017 at 9:38:05 AM UTC+12, Serg io wrote:
On 4/10/2017 4:14 PM, Robert Clark wrote:
The U.S. military is making progress in high power lasers. The Navy
expects to field a ship-born 150 kW laser:

Power is less than linear at near optical speeds. Though recycling photons through a low loss path can multiply power for a photonics thruster to mitigate this high speed effect if the materials are up to it.

Using a diode laser, at 35 kW/kg and $0.10 per peak watt, a 50 MW system weighs 1.43 metric tons and cost $5 million. A 10 GW system weighs 286 metric tons and costs $1,000 million. The first puts up 330 pounds into LEO. The second 66,000 pounds per launch.

So, quite linear.

With one launch every two hours, and a 12 minute boost - a 1 GW power plant, costing between $500 million (for coal) to $5,500 million (for nuclear) is required to power the 10 GW laser. About twice the size of the requirements of this plant

A $1,500 million battery pack to store the required energy and discharge it over 12 minutes, every two hours, is also required for the larger system.

The smaller system can use a portable generator on a ship, or a portable aeroderived generator, or tie into the grid directly, to power the laser on demand - and fire continuous at the lower power rating.

About 1/10th the Tiwai Point Smelter. Or the size of a shopping mall at peak power.

A 50 MW diode laser firing continuously, with a 2 hour recycle time for launch vehicle, and 10 active vehicles, using a dozen active flight articles, for insurance, at $1 million each, we have for less than $20 million the ability to put up 330 pounds x 5 = 1,650 pounds per hour 24/7 - that is 39,600 pounds per day, 14,463,900 pounds per year - at a cost of $78.6 million per year. $3.03 per pound. The value is obviously far greater! More like $1,000 per pound!

The CAPEX is if far less than conventional rockets as well! The system is also quite flexible for payloads that are subdivided into 330 pound increments and self assemble on orbit.

With an average passenger weight of 187 pounds, and another 100 pounds for suit and supplies, people are easily and cheaply put into space for less than $300,000 pounds at the rate of 5 per hour using a single launcher.

Or a network of communications satellites that provide global wireless broadband internet services directly to and from people on the ground without any special receivers or transmitters.

On Tuesday, April 11, 2017 at 9:38:05 AM UTC+12, Serg io wrote:
On 4/10/2017 4:14 PM, Robert Clark wrote:
The U.S. military is making progress in high power lasers. The Navy
expects to field a ship-born 150 kW laser:

What makes this nonlinear potentially, is the ability to use air, and lower the exhaust speeds to get more thrust for a given amount of power.

Energy = 0.5 * mass * velocity^2

and

Force = mass * acceleration.

Now,

acceleration = derivative( velocity )

so;

Force = mass * derivative( velocity )

then also

Force = derivative( mass ) * velocity

finally

Power = derivative( energy )

so
Power = derivative( mass ) * velocity^2

Knowing that;

derivative( mass ) = mass flow rate

And being limited to 50 MW of power in a purely rocket based system, since it takes an ideal delta vee of 9.2 km/sec to achieve low earth orbit (7.9 km/sec speed, 1.3 km/sec loss due to air drag and gravity) the most material is projected to orbit at this power setting by setting the exhaust speed to delta vee. Making it higher, means you waste energy by putting too much in the exhaust jet. Making it lower means you waste energy lifting more propellant than you need.

Now, air around the vehicle, changes that calculus.

We can start at very low exhaust speeds using air as a propellant, and get very large thrusts at lift off, whilst using the propellant at the same power settings, to produce less thrust, at altitude with higher exhaust speeds..

Limiting the exhaust speed from heated air to 12x sound speed, and limiting the use of air as propellant to speeds lower than 12x sound speed means that we can lift a 4,000 pound vehicle off the ground, and accelerate it to 4,000 m/sec. This reduces the delta vee of the rocket portion to 5,200 m/sec, and when the propellant is used, it's exhaust is heated to the point where it produces 3,500 pounds of force - with an exhaust speed of 5,200 m/sec.. Or 0.875 gee. Which means if the flight angle is pitched 61 degrees or less above the horizon, we can maintain or gain altitude, as we accelerate tangential to the ground.

Here we have 2,528.5 pounds of water, 500 pounds structure, 971.5 pounds of payload (over twice the weight to orbit! With the same power - using air at the outset)

We cut the size of the power plant in half, for the larger system, and reduce overall costs by the same factor.

The cost per pound on orbit is also cut in half - about $1.52 per pound.

On Tuesday, April 11, 2017 at 3:46:44 PM UTC+12, William Mook wrote:
On Tuesday, April 11, 2017 at 9:38:05 AM UTC+12, Serg io wrote:
On 4/10/2017 4:14 PM, Robert Clark wrote:
The U.S. military is making progress in high power lasers. The Navy
expects to field a ship-born 150 kW laser:

What makes this nonlinear potentially, is the ability to use air, and lower the exhaust speeds to get more thrust for a given amount of power.

Energy = 0.5 * mass * velocity^2

and

Force = mass * acceleration.

Now,

acceleration = derivative( velocity )

so;

Force = mass * derivative( velocity )

then also

Force = derivative( mass ) * velocity

finally

Power = derivative( energy )

so
Power = derivative( mass ) * velocity^2

Knowing that;

derivative( mass ) = mass flow rate

And being limited to 50 MW of power in a purely rocket based system, since it takes an ideal delta vee of 9.2 km/sec to achieve low earth orbit (7.9 km/sec speed, 1.3 km/sec loss due to air drag and gravity) the most material is projected to orbit at this power setting by setting the exhaust speed to delta vee. Making it higher, means you waste energy by putting too much in the exhaust jet. Making it lower means you waste energy lifting more propellant than you need.

Now, air around the vehicle, changes that calculus.

We can start at very low exhaust speeds using air as a propellant, and get very large thrusts at lift off, whilst using the propellant at the same power settings, to produce less thrust, at altitude with higher exhaust speeds.

Limiting the exhaust speed from heated air to 12x sound speed, and limiting the use of air as propellant to speeds lower than 12x sound speed means that we can lift a 4,000 pound vehicle off the ground, and accelerate it to 4,000 m/sec. This reduces the delta vee of the rocket portion to 5,200 m/sec, and when the propellant is used, it's exhaust is heated to the point where it produces 3,500 pounds of force - with an exhaust speed of 5,200 m/sec. Or 0.875 gee. Which means if the flight angle is pitched 61 degrees or less above the horizon, we can maintain or gain altitude, as we accelerate tangential to the ground.

Here we have 2,528.5 pounds of water, 500 pounds structure, 971.5 pounds of payload (over twice the weight to orbit! With the same power - using air at the outset)

We cut the size of the power plant in half, for the larger system, and reduce overall costs by the same factor.

The cost per pound on orbit is also cut in half - about $1.52 per pound.

The value remains the same.

A more detailed analysis uses calculus of variation and the aerodynamic and gravity losses involved at each moment of the flight, optimising exhaust speed to get the most out of the limited power laser, doing this increases the weight to orbit to, 1,374 pounds - by increasing the launcher size by this factor - and reducing exhaust speeds at launch accordingly.

BTW, about the cost, one of the producers of the 10 kW commercial lasers,
not part of weapons system, gave a price of $472,000. So a thousand would
be $472 million for a total power of 10 MW. Actually for such a large order
the price would likely be significantly discounted from this. Also, it may
be buying a fewer number of say, 30 kW, or 100 kW lasers may result in a
lower total cost.

According to the standard estimate this could launch 10 kg to orbit. Mook in
his posts to this thread estimates it could be three times more, ca. 30 kg.
This could still be useful for getting propellant to orbit when launched at
high frequency.

Bob Clark

================================================== ==============
"Serg io" wrote in message news
On 4/13/2017 12:48 PM, Robert Clark wrote:
I think you are right. I believe the handheld part is just used to
conduct the laser beam to the target. The actual laser is generated in a
separate cabinet:
Bob Clark
I doubt that the laser is at 30kw considering the power of the
similar-level lasers tested by the DoD(blowing up whole drones) and the
fact that the guy is using it at point-blank range compared to the
couple hundred meters ranged in all those test footage from the DoD.

The key problem is the path in air gets heated unevenly by high power
laser and disperses the beam.

you cannot put much power on a target miles away. they still do not
have lasers that shoot down airplanes and missles.

---

----------------------------------------------------------------------------------------------------------------------------------
Finally, nanotechnology can now fulfill its potential to revolutionize
21st-century technology, from the space elevator, to private, orbital
launchers, to 'flying cars'.
This crowdfunding campaign is to prove it:

Lets say that a laser(and other equipment that needs to be replaced every so
often) can be used 10 years before needing to be replaced, there are 2
launches every day, and that all of the cost is from the 472 million dollar
laser array.(probably can get better info from Atomic Rockets but I don't
have time for that). Each launch consumes a megawatt and takes 1 hour, so it
takes $120 per launch if we are drawing power from a US grid(12 cents per
kw-hour). Each launch can lift 10kg.

Likely, the cost for the 1,000 lasers at 10 kW each will be less than
$472,000,000 since they would be bought in large quantity. And the quoted
price was for the entire laser cutting system. The cost would be less for
the bare laser.
Also, the flight time to orbit is expected to be about the same as for usual
rockets about 10 minutes. So you could then have many more flights to
amortize the cost of the lasers.

Bob Clark
---

----------------------------------------------------------------------------------------------------------------------------------
Finally, nanotechnology can now fulfill its potential to revolutionize
21st-century technology, from the space elevator, to private, orbital
launchers, to 'flying cars'.
This crowdfunding campaign is to prove it:

On Saturday, April 22, 2017 at 7:50:49 AM UTC+12, Robert Clark wrote:
================================================== ======================================
"0something0" wrote in message
...

Lets say that a laser(and other equipment that needs to be replaced every so
often) can be used 10 years before needing to be replaced, there are 2
launches every day, and that all of the cost is from the 472 million dollar
laser array.(probably can get better info from Atomic Rockets but I don't
have time for that). Each launch consumes a megawatt and takes 1 hour, so it
takes $120 per launch if we are drawing power from a US grid(12 cents per
kw-hour). Each launch can lift 10kg.

Diode lasers have exceptionally long life if used within certain parameters.. So, in this instance, other factors, such as power supplies, and so forth give life span. However, those lives can be shortened by increasing their power output. In fact, they can be used like old-style flash bulbs, that put out a helluva lot of power and are replaced after each use. Why shorten the life? Because it gains in power per dollar at the cost of energy per dollar.

Now the metric, or calculus, of the relationship, for lowest cost, given near unity efficiencies and ignoring weight considerations, is power output per dollar versus number of hours of use.

According to DOD studies, modern high efficiency diode lasers purchased at above gigawatt scale cost under $0.10 per watt, with virtually unlimited use - 10 years or more. However, by over-amping the diode, lifetimes can be shortened. With a 57% utilisation over a year, each watt of capacity consumes 5 kWh. At $0.12 per kWh that's $0.60 per year. A 10 year life span consumes $6.00 per watt, and with $0.10 per watt of capacity, its clear the energy costs dominate.

What if the cost of the laser was say $10 per watt and not $0.10? 100x more. Then the trick of overamping the diodes and making them disposable parts of the system, pays dividends.

Typically, by running at over the rated power, you shorten life cycle. Running at 1000x the rated power shortens life time from 10 years to 10 hours. So, $10 per watt becomes $0.01 per watt as you overpower the diode by 1000x (1 kW) and the 10 kWh cost $1.20 -

If your laser cost $10,000 per watt - and you over amp it 1 million times rated power shortening its life to 10 minutes - then you consume $20 worth of power for every $0.01 worth of expensive laser.

Your figure is dominated by low utilisation rate. You assume 2 launches per day of 10 kg - a total of 20 kg per day for a $400 million investment. It takes 10 minutes to launch a vehicle to orbit. So, you're assuming 20 minutes of use of a very expensive item out of 1,440 minutes (24 hours) each day. That's 1.4% capital utilisation. If you applied 57% utilisation as I've done above, with no other changes in your assumption, you'd have $1,575 per launch and $157.50 per kg for the hardware and $120.00 per kg for the power.

However, you haven't really taken modern reportage from the DOD as it relates to current costs of laser systems into account. When you do that the cost of power dominates, and the cost of capital is a correction factor.

Now, having a steady state power source big enough to blast a payload into space, that drives a steady state laser source big enough to accept all the power at its peak, and using it only a few minutes a day, is not efficient.. Clearly it pays dividends if you understand the engineering and physics of diode life cycle and power output, and if you organise your use of these to increase their capital utilisation.

Adapted for use inside a Fabrey-Perot interfometer. That is, a material that sits in a large open pond absorbing sunlight, and designed to flash all of its power over a 10 minute period to produce a powerful laser pulse!

Here, we are dealing with pumps, tanks, and optics - only! The cost of energy is zero, the cost of power is zero. The cost of pumps and tanks and optics is about 5% of total system cost (for the steady state) or $0.005 per watt. So a Giga-watt scale laser under these circumstances would cost $5 million - and with a 10+ year life, and 57% utilisation, would be far less than the fuel cost of modern airliners. So, such systems would not only be capable of launching stuff into space, but also of powering passing aircraft and even powering a city via optical fiber.

Likely, the cost for the 1,000 lasers at 10 kW each will be less than
$472,000,000 since they would be bought in large quantity. And the quoted
price was for the entire laser cutting system. The cost would be less for
the bare laser.

The DOD has declassified literature from early 2000s that show at the GW scale, large diode lasers cost $0.10 per peak watt. At these prices, even CW lasers have energy cost over their life cycle dominating. There are pulsed power tricks that reduce even expensive laser systems - like chemical lasers - to where the cost of energy dominates again. Finally, combining ideas to create chemical lasers that gather energy from sunlight very cheaply, we can reduce cost of power to zero. Even with terrestrial systems. In space costs can be lowered even more using thin film reflectors to concentrate sunlight reliably to create compact chemical processing systems on orbit, that provide power where its needed on demand.

The cost in your system is high because you're building a continuous system with off-the-shelf (less than optimal) technology and using it less than 2% of the time. If you built a more reasonable system, using current technology (and why the hell if you're spending half a billion dollars wouldn't you use best practices?) - costs for space travel can be brought to lower than air travel, and even air travel can be reduced in cost.

Also, the flight time to orbit is expected to be about the same as for usual
rockets about 10 minutes. So you could then have many more flights to
amortize the cost of the lasers.

That's right! Now you're getting it! Using your approach you can get prices down to $250 per kg. Using best practices with diode lasers, that can be reduced to $12 per kg, and combining best practices with current tech, gets you to $0.60 per kg and less.

With this technology you not only open up the world to the cosmos, but you make travel from any point on Earth to any other, easy.

In the future people will live in the Andes, work in New York, have lunch in Paris, and pick up their kids in China, before going home. This capacity to travel anywhere in minutes, in less time than it takes someone living in Malibu to travel to LAX to board a private jet.

Facilities on orbit that accept small craft and are capable of travel deeper into space, across the solar system, will one day provide seamless travel from the surface of the Earth to the surface of any world or space colony.

The ability to deliver energy at very low cost and very high power levels, to run these propulsion systems, also gives us the ability to run our industrial economy at very low cost, and zero environmental impact. Combine these capacities with artificial intelligence and smart materials, like utility fog, and you see that a world of great wealth and adventure awaits us.

Bob Clark
---

----------------------------------------------------------------------------------------------------------------------------------
Finally, nanotechnology can now fulfill its potential to revolutionize
21st-century technology, from the space elevator, to private, orbital
launchers, to 'flying cars'.
This crowdfunding campaign is to prove it:

BTW, about the cost, one of the producers of the 10 kW commercial lasers,
not part of weapons system, gave a price of $472,000. So a thousand would
be $472 million for a total power of 10 MW. Actually for such a large order
the price would likely be significantly discounted from this. Also, it may
be buying a fewer number of say, 30 kW, or 100 kW lasers may result in a
lower total cost.

According to the standard estimate this could launch 10 kg to orbit. Mook in
his posts to this thread estimates it could be three times more, ca. 30 kg.
This could still be useful for getting propellant to orbit when launched at
high frequency.

The first report discusses micro-scale LED's whose light output scales up to
300 W per square centimeter, 3 megawatts per meter. From the appearance of
these micro-scale LED's, they should permit simple automated production to
produce many copies to cover a macro-scale area to generate light even at
gigawatt power levels.

The second report discusses experimentation that suggests atmospheric
dispersion is actually worse for lasers than for noncoherent light generated
by LED's. See for instance the video in Fig. 2 on this page.

The advantage of the lasers however is that generating a parallel beam, you
can use a parabolic mirror to focus the light at the focal point (more
precisely at the Airy disk). Still, nevertheless a parabolic mirror will
still focus a large portion of the light at the focal point even for
noncoherent light.

So the question is if the beam is noncoherent, how much of the light can
still be focused at the focal point (Airy disk)?

Bob Clark

----------------------------------------------------------------------------------------------------------------------------------
Finally, nanotechnology can now fulfill its potential to revolutionize
21st-century technology, from the space elevator, to private, orbital
launchers, to 'flying cars'.
This crowdfunding campaign is to prove it: